The focus of this experiment was to identify unknown bacteria. The identification of unknown bacteria produces benefits for many aspects of the research of microorganisms and helps physicians correctly treat patients. Multiple biochemical tests were performed to provide the fermentation abilities, presence of certain enzymes, and certain biochemical reactions. Qualitative observations were made on the tests, which were compared to unknown bacteria identification key to aid with the identification process. And use of 16S rRNA gene sequences to study bacterial phylogeny and taxonomy has been by far the most common housekeeping genetic marker used for a number of reasons. These reasons include (i) its presence in almost all bacteria, often existing as a multigene family, or operons; (ii) the function of the 16S rRNA gene over time has not changed, suggesting that random sequence changes are a more accurate measure of time (evolution); and (iii) the 16S rRNA gene (1,500 bp) is large enough for informatics purposes. Finally the several amplified parts could be assembled together to have the entire sequence of the complete 16S rRNA. In addition to highly conserved primer binding sites, 16S rRNA gene sequences contain hypervariable regions that can provide species-specific signature sequences useful for bacterial identification. Species identification continues to be a challenge. The development of new methods for this purpose is essential. The acknowledged limitations of the 16S rRNA gene for resolving close interspecific relationships will inspire workers to investigate other genes such as recA, gyrB or GroEL as new targets for molecular assays.

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...The Identification of Two Unknown Species of Bacteria in Tube #72
Introduction:
There are many reasons for knowing the identity of microorganisms. The reasons range from knowing the causative agent of a disease in a patient, so as to know how it can be treated, to knowing the correct microorganism to be used for making certain foods or antibiotics. This study was done by applying all of the methods that have been learned so far in the microbiology laboratory class for the identification of an unknown bacterium. Broth culture #72 was randomly selected and subjected to qualitative tests for identification. It is suggested that culture #72 is an example of Serratia marcescens and Micrococcus luteus. There were ten bacteria species possibilities: Stahylococcus epidermidis, Bacillus subtilis, Escherichia coli, Serratia marcescens, Sarcina lutea, Pseudomonas fragi, Micrococcus luteus, Alcaligenes faecalis, Clostridium sporogenes, and Micrococcus roseus. There were several qualitative tests that could be conducted to determine the identity of the unknown species, for example, Gram staining, Fermentation, Catalase, Oxidase, Starch Hydrolysis, Litmus Milk, MOI medium, and the Gelatin Test. All tests and techniques used were performed in accordance with The Microbiology Lab Manual.
Materials and Method:
A stock broth culture of the two unknown species #72 was obtained. Two streaks were performed using...

...concluding idea. The type of bacteria that I am going to discuss and chosen is E-coli. I will also going to research the effectiveness of antibacterial cleaning products, for instance sanitizer. I will also, research which is the most effective product for the house hold and some other work places.
Background Information
What are Bacteria?
Bacteria are found in: soil, radioactive waste, water, plants, animals, deep in the earth's crust, organic material, arctic ice and hot springs, basically everywhere except for places that humans have sterilized. Even the most unlikely places where temperatures may be extreme, or where there may be a high concentration of toxic chemicals have bacteria - these are known as extremophiles (an extremophile is any organism adapted to living in conditions of extreme temperature, pressure, or/and chemical concentrations) - these bacteria can survive where no other organism can.
There are three different types of bacteria which are: spherical, rod shaped and spiral. Normally, the spherical ones are the most ordinary bacteria and bacteria shaped like this are called cocci. Rod shaped bacteria are identified as bacilli. Some of these bacteria are rounded and these are identified as vibrio. Spiral bacteria are identified as spirilla and if their coil is very tight they are known as...

...for distinguishing between Gram-positive cocci in chains (catalase negative) versus Gram-positive cocci in clusters (catalase positive).
The coagulase test is used to differentiate Staphylococcus aureus from coagulase-negative staphylococci. The test uses rabbit plasma that has been inoculated with a staphylococcal colony. The tube is then incubated at 37 degrees Celsius for 1½ hours. If negative then continue incubation up to 18 hours.
* If positive (i.e., the suspect colony is S. aureus), the serum will coagulate, resulting in a clot (sometimes the clot is so pronounced that the liquid will completely solidify).
* If negative, the plasma remains liquid. The negative result may be S. epidermidis but only a more detailed identification test can confirm this, using biochemical tests as in API tests and BBL CRYSTAL methods.
MATERIALS
Sterile swab, oxidase strap, microorganisms (Pseudomonas aeruginosa, E. coli)
METHODS
A. Catalase
1. A drop of 3% H2O2 was placed on a glass slide.
2. A sterile loop was touched to the culture of the tested organisms. Visible mass of cell was picked.
3. The cell organism was mixed in a drop of hydrogen peroxide.
4. Immediate and vigorous bubbling was observed.
5. Obersevation was recorded in a table.
B. Coagulase
1. One drop of Test Latez was dispensed onto one of the circle on the reaction card and one drop of Control Latex on the other circle.
2. A sterile loop was...

...is important to heat fix the bacterial smear before staining so as to, kill the bacteria, firmly adhere the smear on to the microscopic slide to prevent washing off during staining, and to allow the sample to readily take up the stain.
Reference:
www2.hendrix.edu
What is the purpose of heat- fixing the smear?
It helps the cells adhere to the slide so that they can be stained.
The purpose of heat fixing is to kill the organisms without serious distortion. They adhere better to the slide and also take up dye more easily.
Fixation process
Fixation is usually the first stage in a multistep process to prepare a sample of biological material for microscopy or other analysis. Therefore, the choice of fixative and fixation protocol may depend on the additional processing steps and final analyses that are planned. For example, immunohistochemistry uses antibodies that bind to a specific protein target. Prolonged fixation can chemically mask these targets and prevent antibody binding. In these cases, a 'quick fix' method using cold formalinfor around 24 hours is typically used.
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Types of fixation
There are generally three types of fixation process:
Heat fixation: After a smear has dried at room temperature, the slide is gripped by tongs or a clothespin and passed through the flame of a Bunsen burner several times to heat-kill and adhere the organism to the slide. Routinely used with bacteria and archaea. Heat fixation generally preserves...

...Bacterial Contamination
April 15, 2013
Bacteria Contamination
The definition of bacterial contamination is food contamination refers to foods that are spoiled or tainted because they either contain microorganisms, such as bacteria or parasites, or toxic substances that make them unfit for consumption
This is very serious and people should take more precaution, food contamination is a serious because it results in foodborne diseases that each year affect an estimated seventy-six million people in the United States, while leading to some 325,000 hospitalizations and 5,000 deaths. Awareness of potential sources of food contamination is an important component of good nutrition.
Food contamination can be microbial or environmental, with the former being more common. Environmental contaminants that can enter the food supply chain include pesticides, heavy metals, and other chemical agents. Many opportunities exist for food to become contaminated as it is produced and distributed. Bacteria are present in the animals raised for food. Meat and poultry can become contaminated during slaughter through cross-contamination from intestinal fecal matter. Similarly, fresh fruits and vegetables can be contaminated if they are washed using water contaminated with animal manure or human sewage. During food processing, contamination is also possible from infected food handlers. Lastly, poor hygiene in the home is also a factor.
Many...

...BACTERIA
Period: 4
Characteristics:
3 major shapes
Cocci Basilli Spirilla
3 major components
Mesosomes flagella
Plasmids
Growing Up:
Bacteria can obtain energy through phototrophs(sunlight), lithotrophs(inorganic compounds), and organotrophs(organic compounds)
Marriage/Reproduction
Binary Fission: The process by which all bacteria reproduce. It results in the separation of a single cell into two.
Transformation: genetic alteration of a cell resulting from the direct uptake, incorporation and expression of exogenous genetic material (exogenous DNA) from its surroundings and taken up through the cell membrane(s). Transformation occurs naturally in some species of bacteria, but it can also be affected by artificial means in other cells.
Conjugation: The process whereby two ciliates come together in a temporary fusion to exchange micro nuclear material, then separate, each being a fertilized cell.
Explain how the F plasmid controls conjugation in bacteria.
In bacterial conjugation the host bacterium attaches to another bacterium via pili. The plasmid region contains its own origin of replication in other words it can replicate independently from the DNA that is in the cytoplasm. This DNA tends to code for virulence factors. When the pili has attached to the recipient cell then DNA replication of the F-plasmid occurs and it is...

...Lab 11
Methodology
By using aseptic, a little cultured bacteria was inoculated on the TSA agar. A quadric streak was making. Inoculation loop was heated and keep it cold for a while before the next quadratic streak. Six agar plates were observed for 24 hour at temperature of 30ºC. Choose one from the dense colony and make a sub-culture on the new agar plate. The step was repeated to get a single colony, which is pure colony.
a) Sequestration of bacteria from fish organs
Methodology
Dissecting set was prepared and soaks it in a beaker that contains 70% alcohol. Took a fish and put it in a dissecting tray. The alcohol was sprayed on the fish surface. The scrapple was sterile and cut along the fish abdomen. Then, using the sterile scissors, cut to the inside to expose the fish organs. Beak the kidney to took the tissue sample by using the inoculation loop. The streak was made on the TSA medium with 2% NaCl. After each streak, the inoculation loop need to heated. The plate was keep for 24 hour at temperature of 30ºC for colony growth.
b) Sequestration of bacteria from shrimp
Methodology
Dissecting set was prepared and soaks it in a beaker that contains 70% alcohol. Took a shrimp and put it in a dissecting tray. The alcohol was sprayed on the shrimp surface. The carapace was pulled out by using sterile forceps. The hepatopancrease location was specify and took half of it using inoculation loop. The streak was...